Data Sheet
Table Of Contents
- 1 Design guidelines
- 2 Ordering Information
- 3 Pinout and Terminal Descriptions
- 4 Packaging
- 5 Power control
- 6 Interfaces
- 7 Block diagram
- 8 Example schematics
- 9 802.11 Radio
- 10 Firmware
- 11 Host interfaces
- 12 Electrical characteristics
- 13 RF Characteristics
- 14 Physical dimensions
- 15 Layout guidelines
- 16 Soldering recommendations
- 17 Certifications
- 18 Qualified Antenna Types for WF121-E
Silicon Labs
Page 28 of 45
12 Electrical characteristics
12.1 Absolute maximum ratings
Rating Min Max Unit
Storage Temperature -40 85 °C
VDD_PA -0.3 6 V
VDD_3.3V -0.3 3.6
5V tolerant GPIO Voltages -0.3 5.5 V
Other Terminal Voltages VSS-0.3 VDD_3.3V+0.3 V
Maximum output current sourced or sunk by any GPIO pad 25 mA
Maximum current on all GPIO pads combined 200 mA
Table 12: Absolute maximum ratings
12.2 Recommended operating conditions
Rating Min Max Unit
Operating Temperature Range * -40 85 °C
VDD_3.3V 2.3 3.6 V
VDD_3.3V while capable of writing internal flash 3.0 3.6 V
VDD_PA 2.7 4.8 V
Table 13: Recommended operating conditions
*Note: The module may heat up depending on use, at high constant transmit duty cycles (high throughput,
low bitrate for more than a few seconds) the maximum operating temperature may need to be derated to keep
below the maximum ratings.